Weft feeders for weaving looms



Feb. 2, 1960 R. DEwAs WEFT FEEDERs FOR WEAVING LOoMs 2 Sheets-Sheet 1Filed Feb. 20, 1956 INVE NTOR: R. Deu/as Ar'ronusas Feb. 2, 1960 R.DEwAs wEFT FEEDERS FOR wEAvING ALooms 2 Sheets-Sheet 2 Filed Feb. 20,1956 INVENTOR:

ATTQLNEss taes i This invention relates to improvements in weft feedersYfor weaving looms in which the weft is fed continuously from largefixed bobbins, has reference Ytotheheads arranged on the ends of theneedlesor bands of the kind described in the complete specification ofmy earlier U.S. Patent No. 2,192,728 and has for its` general object toimprove the elastic thread clamp on the head ofthe conveying needle. Y

In particular the invention refers to one of the variants described inthe said complete specification, namely that in which the part of thethread clamp coming into contact with the side of the head of theconveying needle comprises a shoe-like element simply heldin place bythe free end of the blade spring being elastically-pressed against thesaid surface.

It has been found that such an arrangement may present certaininconvenience because the force of the blade spring on the shoe-likeelement does not operate with suicient precision and accuracy and suchforce'may even change in the course of operation.

With the particular View of affecting the application of the force ofthe blade spring with precision and accuracy and further to enable theposition of the point of application of this force `to be regulatedproperly, thefinvention has the further objects of introducing thefollowing principal improvements. p

Firstly, the shoe-like element of the thread clamp is located inoperative position at tworpoints at one of which the force of the bladespring is-applied directly or indirectly to the shoe-like element whilstat the other the shoe-like element is held so as` to allow the elementto tilt.

Secondly, in one arrangement described Yhereinafter the shoe-likeelement is provided with a rearwardly extending prolongat'on that isfixed, with a certain degree of freedom of movement, either on one sideof the head of the conveying needle or on the blade spring.

Thirdly, the indirect application of the force of the blade spring on tothe shoe-like element is effected by interposing an intermediary partbetween the blade spring Vand the shoe so as to ensure a correcttransmiss'o of the be placed in any one of the recesses more or lessdistant from the end.

Sixthly, the other part, preferably the shoe-like element, is providedwith a groove suitably profiled to receive the ball that constitutes theintermediary part between the shoe and its associated blade spring andSeventhly, the middle part of the blade spring 'is narrow to facilitateits lateral movement under the action of the thread.

These characteristics, as well as others which will appearhereinafter,are fully disclosed inthe following deateet ice scription of the nonlimitative forms of construction given by way of simple examples andshown in the diagrammatic figures of the drawing attached to this`complete speciiication, in which:

Figure 1 is a plan view of the head of a conveying needle with one formof thread clamp, according to this invention, applied thereto;

Figure 2 is aflongitudinal vertical section taken on Ithe line II-II ofFigure 1;

Figure 3 is aplan view of the blade-spring of the thread clamp; y

Figure 4 is a fragmentary detail view in'vertical section taken on theline IV-IV of Figure 3;

Figure 5 is a plan View of the shoe-like element ofthe thread clamp;

Figure 6 is a vertical longitudnal section through the thread clamptaken 'on line VI-VI of Figure 5;

Figure 7 is a verticall transverse section, on a larger scale, throughthe thread clamp taken on the line VII- VIIfof Figure 5;

Figure 8 is a plan view of a modified form of thread clamp according tothis invention;

Figure 9 is a vertical longitudinal section through Figure 8 taken onthe line IX-IX of that figure;

Figure 10 is a plan View of the shoe-like element;

Figure 11 is a Vertical longitudinal section through Figure 10 taken onthe line XI;XI of that figure; and

Figure l2 shows a vertical transverse section through Figure 10 taken onIthe line XII-XII of that figure and drawn to a larger scale.

In these figures' 1 is the conveying needle of which the side 1a facesthe reed on the batten and the side 1b faces the cloth, 2 is the pointof support for the' thread and 4 is the cutting blade.

The thread clamp, arranged toholdthe thread 3 during its passage intothe head of the conveying needle, is constituted by the co-operation ofthe Wall 1c of the needle with the shoe S, being'pressed there againstby the blade spring 6 mounted on the wall lfby means of the screws 7 and7. This arrangement enables the pressure exerted by the blade spring 6vto be regulated by adjustment of the screw 7 whose head is in Contactwith the outer surface ofthe blade spring. Y

The front end of the blade spring' is provided with several recesses 8,the three shown in the drawings, each being adapted to accommodate theball 9 which constitutes an intermediary 'part transmittingthe force ofthe pressure exercised by the blade spring to the shoe-like element 5. n

The shoe-like element 5 has the longitudinal' groove 10 of suitableprole (that may be of V-shape as shown or perhaps of U-shape withrounded or at bottom) to co-operate with the ball 9.

The ball 9 which may be of steel, industrial stone, agate or othersuitable pressure transmitting material, has the advantage of alwayscorrectly transmitting the pressure from the blade spring to theshoe-like element regardless of the relative positions of these parts.

The three recesses 8 are made by countersinking holes so spaced that thecountersinks overlap to suchex'tent as to enable the ball 9 to be easilyshifted from-one to another so that the force of the pressure of thespring can be applied precisely at the point necessitated by the natureof the thread, its thickness and 'so on.

The shoe-like element 5 has a rearwardly extending prolongation 5aterminating in a stub 5b which cannot come into contact with the wall 1cunless thethread 'is engaged by the thread clamp.

The stub 5b is loosely fitted onr the stud 11 the stem of which ismounted in the wall 1c. In' this way 'the stud 11 and the ball 9constitute two poi-nts ofv 'support that assure the position of -ldieshoe-like element. In

` allow it to rise under the action of the thread.

surfaces, and a ball housed selectively 'recesses and in said groove. j

use when the thread engaged by the thread clamp, the pivoting of theshoe-like element takes place around the stub 5b.

lf the blade spring 6 is, as shown, narrow at its middle part, theshoe-like element, when actuated by the thread, can move laterally, byrotationabout the stud 11, with sufiicient amplitude, which althoughsmall, facilitates the discharge of impurities.

The fact that the stud 11, around which the shoelike element S pivotswhen the thread enters the thread clamp, is located at a distance fromthe zone of clipping, has the advantage that the shoe-like element, whenrising, assumes only a small inclination and that its rear end a israised so that impurities are easily discharged to the rear which is ofadvantage, inter alia, when handling a fluffy thread or a thread havingmotes.

The modified construction shown in Figures 8 to 12 differs from thatalready described by the fact that the shoe-like element 5 has norearwardly extending prolongation and that, instead of being mounted onthe wall 1c, it is attached loosely to the blade spring by the stud 12which passes freely through the rear part so as to construction the twopoints of support are constituted respectively by the ball 9 and thestud 12.

It is to be understood that without exceeding the scope yof theinvention, variants and improvements in detail can be conceived. Y

For instance, the fixing of the rearwardly extending I tegral with thestub 5b and pass through a hole in the l wall 1c.

Alternatively the rear part of the shoe-like element may be rounded toallow, when the weft feeder returns to its position outside the fabric,of the insertion of a cleaning sheet mounted, for example, inside thehead of the conveying needle, behind the shoe-like element on the end ofa rod co-operating with a stationary abutment for moving the sheet intothe thread clamp and with an elastic arrangement for bringing the sheetback to its rest position.

What I claim is:

l. A thread clamp for the conveying needle of a weaving loom with astationary weft supply bobbin, having, in combination, a cantileverblade spring anchored at one end thereof on the body of the conveyingneedle, an elongated shoe-like element having a portion thereof adaptedto bear flat against a part of the conveying needle, said shoe-likeelement being shorter than said In this blade spring and being tiltablymaintained at two points thereof longitudinally spaced apart, namely, ata first point by the free end of the blade spring which urges saidelement against the needle body, and at a second point located betweensaid first point and the point where said blade spring is anchored onthe needle body,iwhere by said shoe-like element is capable of orientingitself independently of said blade spring in any direction and to vbearflat over its entire contact area against said needle part.

2. A thread clamp according to claim 1,'further comprising means foradjusting the position of said first maintaining point longitudinally ofsaid blade spring and shoe-like element. Y

3. A thread clamp according to claim l, further comprising means foradjusting the position of said first maintaining point longitudinally ofsaid blade spring and shoe-like element, lsaid first point adjustingmeans comprising a plurality of recesses in one of the two facingsurfaces of the free end of the blade spring and shoe-like element, alongitudinal groove in .the other of said two in one Yof said 4. Athread clamp for the conveying needle of a weaving loom with astationary weft supply bobbin, having, in a combination, a cantiliverblade spring anchored at one end thereof on the body of the conveyingneedle, an elongated shoe-like element having a portion thereof adaptedto bear fiat against a part of the conveying needle, said shoe-likeelement being shorter than said blade spring and being tiltablymaintained at two points thereof longitudinally spaced apart, namely, ata first point by the free end of the blade spring which urges saidelement against the needle body, and at a second point by a stud locatedon said needle body between said first point and the point where saidblade spring is anchored on the needle body, whereby said shoe-likeelement is capable of orienting itself independently of sail bladespring in any direction and to bear flat over its whole area againstsaid needle part.

5. A thlead clamp for the conveying needle of a weaving loom with aVstationary weft feeding bobbin having, in combination, a cantileverblade spring adjustably anchored at one end thereof on the body of theconveyng needle, an elongated shoe-like element having a portion thereofadapted to bear fiat against a part of the conveying needle, saidshoe-like element being tiltably maintained at two points thereoflongitudinally spaced apart on said clamp so that said shoe-like elementis capable of orienting itself in any direction and to bear flat overits whole contact area against said needle part, a rearwardly projectingprolongation on said element, a stud on the blade spring tiltablytto-operating with the rear end of said prolongation and means fortransmitting the force of the pressure of the blade spring to theshoelike element to said element against said conveying needle.

6. A thread clamp for the conveying needle of a weaving loom with astationary weft feeding bobbin having, in combination, a cantileverblade spring adjustably anchored at one end thereof ou the bodyof theconveying needle, an elongated shoe-like element having a portionthereof adapted to bear flat against a part of the conveying needleunder the action of said blade spring, said shoe-like element beingtiltably maintained at two points thereof longitudinally spaced apart onsaid clamp so that said shoe-like element is capable of orienting itselfin any direction and to bear llat over its whole contact area againstsaid needle part, a plurality of recesses in the free end of the bladespring facing the shoe-like element, a longitudinal groove in the saidelement facing the blade spring and a ball housed in one of the saidrecesses and in the said groove, said ball constituting one of said twolongitudinally spaced points at which said shoe-like element ismaintained.

7. A thread clamp for the conveying needle of a weaving loom with astationary weft feeding bobbin having, in combination, a cantileverblade spring adjustably anchored at one end thereof on the body of theconveying needle, an elongated shoe-like element having a portionthereof adapted to bear fiat against a part of the conveying needleunder the action of said blade spring, said shoe-like element beingtiltably maintained at two points thereof longitudinally spaced apart onsaid clamp so that said shoe-like element is capable of orienting itselfin any direction and to bear flat over its Whole contact area againstsaid needle part, a rearwardly projecting prolongation on such element,a stud on the conveying needle tiltably co-operating with the rear endof said prolongation, a plurality of recesses in the free end of theblade spring facing the shoe-like element, a longitudinal groove in thesaid element facing the blade spring and alall housed in one of therecesses and in the said'groove saidY ball and said stud respectivelyconstituting said two longitudinally spaced points at which saidshoe-like element is maintained.

v8. A thread clamp for the conveying needle of a weaving .loom with astationary weft feeding bobbin having, in combination, a cantileverblade spring adjustably anchored at one end thereof on the body of theconveying needle, an elonga-ted shoe-like element having a portionthereof adapted to bear at against apart of the conveying needle underthe action of said blade spring, said shoe-like element being tiltablymaintained at two points thereof longitudinally spaced apart on saidclamp so that said shoe-like element is capable of orienting itself inany direction and to bear at over its whole contact area against saidneedle part, a rearwardly projecting prolongation on said element, astud on the blade spring tiltably co-operating with the rear end of saidprolongation, a plurality of recesses in the free end of the bladespring facing the shoe-like element, a longi tudinal groove in the saidelementfacing the blade spring and a ball housed in one of the saidrecesses and in the said groove said ball and said stud respectivelyconstituring said two longitudinally spaced points at which saidshoe-like element is maintained.

References Cited in the file of this patent UNITED STATES PATENTS l02,119,573 Dewas June 7, 1938 2,192,728 Dewas Mar. 5, 1940 2,567,993Dewas Sept. 18, 1951 2,586,638 Flamand Feb. 19, 1952

